S-94173A346 1/2"-20 x 4 1/2" 12-Point Screws

Key Features & Benefits at a Glance

• Maximum torque transmission with external 12-point drive design for secure tool engagement in high-stress applications
• Superior corrosion protection through black-oxide surface treatment, extending service life in demanding industrial environments
• Exceptional mechanical strength with 170,000 psi tensile strength and Rockwell C38 hardness for heavy-duty fastening requirements
• Precision thread alignment with Class 2A thread fit ensuring reliable assembly and consistent clamping force
• Enhanced stability and load distribution from integrated flange design, reducing the need for separate washers
• Optimized for fine-thread applications with 1/2"-20 UNF configuration providing superior vibration resistance
• Versatile partial threading allowing for both secure fastening and adjustable positioning in assembly operations

Professional Applications & Engineering Value

This 12-point screw delivers critical performance advantages for high-torque industrial applications where reliability is paramount. Engineered from black-oxide alloy steel, it provides exceptional resistance to corrosion and wear in demanding environments including heavy machinery, construction equipment, and automotive assemblies. The external 12-point drive design ensures maximum torque transmission without stripping, while the Class 2A UNF fine threads maintain precise clamping force under vibration. The integrated flange distributes load evenly, preventing surface damage and simplifying installation. With 170,000 psi tensile strength and partial threading, this fastener offers both structural integrity and assembly flexibility for critical connections.

Specification Summary & Compliance

Manufactured to precise inch system dimensions with Class 2A thread fit tolerance per UNF standards. Features 1/2"-20 UNF fine threads with right-hand direction and 4 1/2" length with minimum 1 1/4" thread engagement. The black-oxide alloy steel construction meets industrial requirements for strength and corrosion resistance. Complies with ASME/ANSI standards for dimensional accuracy and material properties suitable for demanding mechanical applications.